Meeting with memory makers has been fun these past several months - they're all so happy. It's a stressful business, but these days the memory makers are quite excited about Vista and after using the OS for a while now we can understand why. You've undoubtedly been hearing that Vista's memory requirements will be greater than those of XP, but how much greater are they in practice and why?

First and foremost, Vista's memory requirements are higher than XP's simply because there is much more to Vista than XP. There are far more background tasks to take care of, a much more complex UI, and a code base that's significantly larger than that of Windows XP. All of these items require memory, and thus when you boot up a Vista machine with 512MB of memory, almost all of it is already being used.

Microsoft and software makers in general are notoriously bad about understating minimum system requirements, so when you see that the bare minimum requirements for Windows Vista list a system with 512MB of memory, you should know right off the bat that this isn't going to be a pleasant experience. Although Vista will do its best to disable background tasks and neat effects to make using your computer less painful with 512MB, we simply wouldn't recommend it. You can get by running a single application, such as IE7 or Outlook, but multitasking is out of the question. In one of our test scenarios we had four applications open and attempted to close one of them. This process took around 2 seconds if we had 2GB in the system, but it took over 12 seconds if we only had 512MB. Most of us really don't like using Windows XP on a system with only 512MB, and needless to say Windows Vista turns that dislike into outright hatred. Windows XP is more tolerable with 512MB, but we would make a very similar characterization about the overall experience on a system with such little memory.

The experience completely changes with 1GB; the improvement is tremendous. Searches appear quicker, applications launch and close faster, and using the OS is just so much better. Once again, we're not telling you anything you haven't heard before, except that 1GB should really be the minimum for any Vista machine and not just those that are Premium certified. Even our budget Buyer's Guides have recommended at least 1GB of RAM for over a year, and Vista pretty much makes that a requirement.

It's the above-1GB range that really has most of us concerned. For the longest time, 1GB was sufficient for most enthusiasts under XP. As applications and usage models got more demanding, and as memory prices dropped, the move to 2GB made sense. Above and beyond 2GB never really made a lot of sense because Windows XP didn't seem to do much with the added memory. Even if you had unused memory, Windows XP didn't really make the most of it resulting in even recently used programs being paged in from disk instead of loaded out of the main memory cache. Vista changes all of this.

If your memory usage under XP kept you just under needing more than 2GB, you'll need 2GB with Vista. We took two identical installs, one with Windows XP and one with Vista, both equipped with 2GB of memory and ran the following scenario on them:

We opened 104 images in Adobe Photoshop CS3 from our recent trip to Las Vegas for CES 2007; with all 104 images opened and loaded, we then timed how long it would take for Microsoft Word to start. In Windows XP, despite some swapping, Microsoft Word 2007 started in just under 8 seconds. On our Vista test bed, starting Word took almost 20 seconds due to constant paging to disk. The only difference? Vista's heightened memory requirements took a stressful situation that worked reasonably well under XP and made it far more painful with the same amount of memory.

We then upgraded the Vista machine to 3GB and ran the test again; thanks to faster application load times and intelligent prefetching, Word started in 1.31 seconds. If you thought that 2GB was the sweet spot for Windows XP, chances are 3GB will be the new minimum for you under Vista.

Thus far all we've talked about, at a high level at least, are static memory requirements and how they are impacted by Vista. Vista uses more memory and in turn, you'll need a bit more memory to get a similar experience to what you had under XP. With SuperFetch however, Vista can actually significantly improve your system's performance if you throw more memory at it.

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105 Comments

Did you guys run the 64-bit tests solely on the Intel Conroe platform? Or did you test an AMD based platform as well? Recall that Conroe has a few performance enhancing features that *only* work in 32-bit mode (branch fusioning, for one - some decoder limitations as well).

That could explain why a Core 2 Duo system might have seemed slower in 64-bit than in 32-bit mode. Reply

SuperFetch is by far my favorite new feature of Vista. I put my first copy of Vista on my laptop, which has a 5400 RPM hard drive. Opening apps Outlook and VB .NET 2005 EE weren't really slow under XP, but there were those few extra seconds it took to load that would often leave me tapping my finger on the palm rest while I waited. Now under Vista, Outlook, VB .NET 2005 EE, and IE7 all seem to be able to fit in the SuperFetch cache, as they all open nearly instantly with just 1 GB of RAM. I'm considering upgrading to 2 GB just to see what else I can get to open really fast. :D Reply

Was superfetch disabled when you tried the Readyboost feature in Vista? Whichever way you ran the test it bears mentioning. If it was off, then how does it do with it on? If it was on, it may make a difference in how it relates to XP.

Also, as I understand it Vista has a system backup now that creates a "ghost" of the drive. Could you check out this feature and get back to us? Reply

I'm not sure it's possible to disable SuperFetch, so I'm pretty sure all testing was done with it on. As far as the "ghost" goes, that's part of System Restore which can be disabled quite easily. I'll have to let the other editors say whether it was enabled or not, though. Reply

What drives me nuts are the plentiful comments about how slow Vista is compared to XP. I mean, anybody hear this before when MS came out with a new OS ? Same thing for XP,W2k,98 ... ad nauseum. Yea, its a new Operating System with more 'toys' built in, what were you expecting ? You aren't gonna load it on your P3/256 RAM rig and enjoy the Vista 'experience'. Damn, this thing runs better than XP on my rig !
It's understood that it won't be as quick (keep in mind the OS has been available for retail purchase ... 2 days now) as XP, but drivers will improve that performance gap to a smaller number within 3 months time. I waited until just last year to upgrade to XP (W2K all the way for me !) but find myself with 2 copies of Vista and would prefer to dual boot one and go Vista all-out on the other one.
I griped back in my W2K days about being forced to upgrade due to content (MS games were announced that would only run in XP) so this time around I will be ready.
DX10? Marketing genius !!! We shall force an upgrade upon the masses !! I upgrade frequently, so DX10 and its graphical splendor is a priority, but if I would have to fork over $200 to actually buy Vista, I would be less than impresssed with DX10 eye candy. Reply

Hopefully, now, finally, Anandtech will start testing motherboards for stability while loaded with the maximum amount of memory. So if the MB supposedly supports 8GB of RAM, you test it with that much, and make sure its stable. I've wanted this done for years... memory is expensive and it sucks to load a MB up and find out it doesn't really work or only works if you cut the speed in half.

... no mention of DRM then? No mention of Linux? Personally I hate Linux, but I've switched to it because of Vista's use of DRM. Not all Microsoft's fault, but they put it in there... My computer, my hardware, I choose what to do with it, not MS, not media companies. Why shouldn't I be able to watch High def content on my old, and once expensive non-HDMI LCD screen?

Get a Mac, Apple is the lesser of 2 evils, they aren't the 800lb gorilla in the room. MS could have told media companies to stuff it. Apple has no choice, it's too small, yet their the ones that forced DRM-Light(TM) on the media companies. MS had the media companied force DRM-Oppressive(TM) on them... how the heck does that work?

I can't believe you left Linux out of the final comparison, is it as capable an OS, yes. Not nearly as user friendly, but it also has 0 DRM, doesn't phone-home isn't beholden to any one entity. I'm not against DRM, as a whole, just Vista's implementation. BS like MS creating D3D to subvert open standards like OpenGL, then removing it from the OS, using it's monopoly-based-ridiculous-margins(TM) to finance D3D's uptake, again rather than take an existing standard and expanding on it. They create their own to reinforce their monopoly. I know why they do this stuff I'm just peeved so many people don't give two flying f...

Youre insane dude.. No offense but there just isnt anything else to say. Posts like these always read like the transcript of a Weather Underground meeting in the sixties. "FIGHT THE POWER!!! FIGHT THE POWER!!!"

Look out! The black helicopters have deployed from the underground helipad in Redmond and are circling!!! Send up the penguin symbol to summon the dynamic duo - Torvald and Stallman! Reply

There is no more or less DRM in Vista than in XP, or even OS X. The platform does not determine the playback of DRM'd media, the content does. The choice is simple: If you want to play back DRM'd media, then you have to support the decryption scheme that the media requires to decode it. In so doing you have to legally accept the limitations defined by that DRM scheme.

It is no different for OS X, Linux, XP or any other OS. They either support the DRM schemes or they do not get to playback the media that uses them. This is why it is unlikely that you will be able to play DRM'd High Definition content anytime soon on Linux. That is the alternative, no support for the content at all.

Also, you can play high definition content on Vista just fine without HDMI/HDCP on your monitor. You simply cannot play back such content if it is coupled to a DRM scheme that requires HDCP, but that is true of every OS. Any other HD content will play back without issue.

Again, there is no difference between DRM on Vista from DRM on any other platform. Reply

The DRM in vista is the major reason that I will only install it if physically forced to. Having bought a new Dell in order to get their very nice 24" LCD last december, I have an upgrade coupon which will lie unused until/unless the DRM can be disabled. MS refuses to display HD on my new monitor using Vista? Screw em. Reply